If you have hay fever, taking hefty doses of fish oil may just help you get rid of it. At least, you could come up with this idea after reading a study done by nutritionists at the Technical University of Munich, published in the European Journal of Clinical Nutrition. And no, the researchers were not paid by a fish oil manufacturer.

Allergy & immunity
Before you can get hay fever, your immune system has to be sensitised. Your immune cells mistake pollen proteins [a few of these are pictured here] for dangerous intruders that they have to fight at all costs. If you're sensitised then your immune system goes on alert if you inhale pollen via your nose or mouth.

The first phase of an immune reaction is an inflammatory reaction – and fish oil is an anti-inflammatory. If your body – or to be more precise, your cell membranes – contains relatively high amounts of omega-3 fatty acids then in theory you are less likely to become sensitised. If you are already sensitised, then omega-3 fatty acids could reduce the chance that you develop hay fever symptoms. Also in theory.

Study
The Germans measured the amount of omega-3 fatty acids present in the membranes of the red blood cells of just under 600 men and women. And they looked to see whether the blood of their subjects contained antibodies against pollen proteins. If they found antibodies it meant that the test subjects were sensitised. They then asked the test subjects whether they were troubled by hay fever symptoms.

Results
The more EPA fatty acids [C20:5 n-3] the subjects had in their cell membranes, the less often they were sensitised. The researchers then set the chance of sensitisation of the 25 percent of the subjects with the lowest EPA in their cell membranes at 1. The 25 percent of the test subjects of the subjects with the most EPA in their membranes was half.

When the researchers looked at the chance of the subjects having hay fever, the relationship was the same.

One factor is the relationship between arachidonic acid [AA] and EPA. The more EPA and the less AA your membranes contain, the lower the chance you'll develop hay fever. That's not so surprising. Arachidonic acid, a metabolite of plant-based omega-6 fatty acids, is a precursor of inflammatory factors.

Conclusion
Imagine: you take 100 people with hay fever and get them to take a whacking eight grams of fish oil each day for a year. How many of your subjects would still have hay fever after a year?